Manchester United manager Sir Alex Ferguson is uncertain as to whether he should play Cristiano Ronaldo in the Champions League tie at Villarreal, for the Portuguese hitman was substituted with a leg injury at Villa Park during United's draw 0-0 with Aston Villa at the weekend.

"It's a problem. I would rather leave him out," said Ferguson for the Manchester United official website.

Bulgarian striker Dimitar Berbatov, who picked up a thigh unjury in Bulgaria's friendly against Serbia, in which Bulgaria were demolished 6-1, is definitely out of the match and so is right-back Gary Neville. Further selection problems for Ferguson are Darren Fletcher, who has returned from a knee injury but is not 100 per cent sure whether he will start the match,  while Tomasz Kuszczak will come in between the sticks for Edwin Van der Sar, who is being rested.

Ferguson said: "We are giving another goalkeeper an opportunity and experience. There is no better experience than a European tie away from home."

United have been in blistering form in Europe and in England after a hesitant start of the season and need only a point in Spain to reach the Champions League knockout stages.

Manuel Pellegrini, the manager of Villareal, wants to avoid any doubts that his side will play out a gentle draw with the defending European champions, even though such a result would assure both teams of progressing to the knockout stage, thus he is not likely to bank on defensive tactic for a draw which would serve both teams right in the end. Villareal will go out on the offensive against the European and England champions and seek the extract the maximum three points from the fixture.

The Chilean coach is famous for setting very high standards for his players and Pellegrini is standing firm by his guns and his assessment of the task in hand. "The worst possible way to qualify for the next round would be to go out and try to play for a draw,” he said, as quoted the UEFA website.

Meanwhile Manchester United manager Sir Alex Ferguson payed tribute to his opponents on the night: "There are good signs that Manuel is creating his own identity at Villarreal," he said. "You get that with Arsène Wenger at Arsenal, you got it with Brian Clough at Nottingham Forest and perhaps you get that with me at United. He's doing the same thing. To finish second in their league without the massive resources of Barcelona, Real Madrid or Valencia is tremendous and born of fantastic consistency. They (Villareal) are a fantastic side and it will be a great match,” he said as quoted by the BBC.